Forward to the future, or stick with the past? New powertrain for the DMC

So after the end of this month, my garage will not longer be a dumping ground for the stuff people have ‘donated’ for The Dancer’s non-profit’s annual yard sale and I’ll actually be able to work in it again. Since I now have a pretty good connection with a local machine shop that should be able to do the frame repairs that are what started my having to do such an in-depth teardown of the DMC, I really want to get back moving on it and plan to start back up finishing stripping everything off of the frame. As a bonus, the machine shop also has a good bit of experience with general automotive fabrication including adapter plates, so they will be able to handle making the adapter plate for whatever power plant I end up deciding to replace the aging and underwhelming original PRV with.

Which is where I’m at with this thread- revisiting working out just what I should be replacing it with- more specifically with this thread, whether I should try and find an appropriate gas engine for it or push toward the future and convert it over to electric. There are definite pros and cons for both routes...

If I keep it gas, I will likely be going with another (more powerful, and ideally lighter) 6-cylinder engine. My original plan had been an L67 supercharged 3800, but my concern with that now is that it is a rather aged engine now and parts will get harder to find- and that there are newer, better options available. If it will fit (I’ve not measured the available space in the DMC’s engine bay to see), it’s tempting to use a BMW inline-6, specifically the 3.0L M54- largely because that’s what powers my E46 convertible, so there would be both a parts commonality and familiarity with the engine. A newer one (like the 3.0L N52 or if I wanted to get more nuts, the turbocharged N55) might also work- all of them would be definite upgrades from the PRV. And of course there are plenty of good, newer V6’s.

Pros of keeping it gas:

• Requires less overall modification, as the fuel system is already in place as is the radiator and other accessories like the AC system
• Considerably less costly. An engine pulled from a junkyard and overhauled would cost less than $1000, and even adding in the cost of a standalone ECU setup (like MS) would be considerably less than the cost of an EV setup
• Range. Honestly, this isn’t as big of an issue since the odds are that the DMC isn’t going to be driven much further than an hour or so away and will mostly just be driven around town.
• Ease of registration/licensing- I haven’t had the chance to really figure out how complex it will be to re-register the DMC with an electric drivetrain, but if I keep the engine a 6-cylinder I shouldn’t have to do anything at all since that’s what is on the current title.

Pros of the EV conversion:

• MUCH simpler overall. This is the big plus. I’d be taking the ‘simple’ approach and just replacing the gas engine and keeping the DMC’s original 5-speed transmission (with some reinforcements that it needs to take more power) so wouldn’t have to worry about (nor get the benefits from…) the complexity of an EV transmission/CVT. But losing the gas engine would not just mean not having it- it would mean not having all of the coolant piping and the radiator up front, not having to worry about oil (for the most part), not having the fuel lines running from the front of the car (the fuel tank is located between and behind the front wheels), and a whole lot of wiring necessary for sensors and engine management. It would require getting an electric A/C and heating system- but if I were to pick up a wrecked EV as a donor it should have all of those. Maintenance would be far simpler as well.
• Rewiring anyway. This kind of plays into the ‘simplicity’ one, but I’ve been planning on re-wiring pretty much the entire car while I’ve got it apart anyway- the wiring is at this point over 40 years old and was lousy British wiring in the first place, and with either putting in a new engine management system or full electric, it just makes sense. And the electric conversion should also cut down on the amount of overall wiring I’d have to do by a fair bit.
• Potential weight reduction. Depending on the weight of the new electric motor and the batteries (and how many I use and where I put them) there may be a bit of a weight reduction. The would definitely be the chance to improve the balance of the car though since the motor should be solidly lighter than the PRV+fluids, and I’d figure the batteries would mostly be going up front where the fuel tank currently is.
• On-theme. Yeah, this shouldn’t really matter that much- but the DeLorean was supposed to be the ‘car of the future’, and having it be electric would just fit.

So, I’m interested in everyone’s thoughts on it. Thanks!

I think the L67 is still a good call - just put a new intake manifold on there while it's out of the car. Although the 3.9 that replaced the L67 could also be an option.

One other possibility, although it may cost more: What better engine could DeLorean have used? Something available in 1980, more powerful, without being much heavier. Mazda 13b? Carbed Buick V6? Unfortunately that year was kind of a low point for engine choices 

Alright, I'll be the first to say the obvious and get it over with....Mr. Fusion! 

(In seriousness - EV sounds cool and fitting!...)  

what Horsepower will the Gearbox take and survive ?

and if you EV it , will you hook up the EV motor with the gearbox you have or put  the complete rear drive out of a Tesla etc ?

Ev would definitely be my choice, if I could afford a donor and had the safety equipment to get it setup and running. 

Leaf is probably the easy button, but a wrecked yet useable Tesla swap would be spectacular. 

Definitely gonna have to tie a speaker to the accelerator to make futuristic space noises when you hit the go pedal though. 

I vote EV. Especially for your use case.

If it only drives around town then the only reason to shy away from the EV swap may be cost IMO.

I thought long and hard about whether I should buy another ICE vehicle when I got the 86 a couple years ago, and the factor that tipped the scales was the need to do sustained lapping at places that were at least 1hr away and then self-transport back. There still aren't many EVs or tracks that could accommodate that...without that need an ICE wouldn't have made sense.

If the measurements are right, what about a 2008+ Mercedes 272 engine (cheap, powerful, reliable and lots available) or the Nissan VG35 (cheap, powerful, reliable and lots available)?

In reply to MadScientistMatt :

My original choice for what I wanted to put in it was going to be a rotary. The car was actually supposed to have a rotary engine in it- there was a company in Europe working on one that JZD had contracted to provide the powerplant for the DMC-12, but they were never able to get the engine to work so they had to look elsewhere and settled on the PRV. I wanted to put a Renesis in it, but researching it I realized that the transaxle just would not take the RPMs that the Renesis would need to really shine.

I'm not worried about staying time-specific (hahahaha) at all- I'm more interested in reliabilty and ease of getting parts down the line since the DMC is the one vehicle out of our small fleet that I expect to own (and hopefully be driving) until I die...

In reply to californiamilleghia :

If the input shaft (the weak point) is replaced with a stronger one (which I have), the transaxle can handle the power and torque from a V8 LS engine- and I'm not really that interested in having that much power for what I intend to use it for, so I should be good. 

If I go EV, I'm more likely to take the simpler route of just hooking the electric motor up to the DMC's transaxle. Using the whole motor/gearbox out of the EV would be more efficient (fuel-wise), but would be a lot more complex getting everything to work properly- and IMO a lot less fun than still having the 5-speed.

I used to work with a guy (nearly 20 years ago now that I think of it) who put a V6 Nissan engine with a Porsche transaxle in one of his.  Possibly from a Maxima?  I don't speak Nissan.  His name is Mark (or Marc?).   He also had a turbo DeLorean and a stock one IIRC. 

It seemed like a nice candidate engine.  Double the power and similarly sized/shaped.

EDIT: Found it.  I don't recall it being supercharged when I saw it.   https://www.my4dsc.com/marc-levys-vq35de-powered-supercharged-dmc-delorean/

I would strongly consider a SOHC version of the Honda J35.   Available in basically everything, good power, and Hondas have good swap support.  

I'm not really an advocate for EV swapping a classic car. But in the case of a DMC-12, a car that was futuristic and still is futuristic 40 years later...this is the way.

Target something 100-150kw range and you'll have more than enough power to really enjoy the car. Plus the INSTANT torque.

Definitely EV. (Drops mic)

I think hoping for a weight reduction with a DIY EV conversion is very unlikely, at least not unless you're willing to accept a very short range.  Electric motors are light (a Tesla Model 3's transaxle is something like 150 pounds), but the batteries make any savings disappear (over a thousand pounds for the ones in the same Model 3).

I'm in the gas-powered camp for now, unless you can get some outrageous deal on a wrecked Tesla.  If you stick with a V6, the Nissan and Honda ones seem to be the "easiest" options when it comes to aftermarket support.  If you are willing to change to a 4 cylinder, a Honda K swap would give you an insane amount of options.

Slightly biased but a base model 3 would make plenty of power and should be super available. Plenty of folks are hacking them to turn up the power as well.

Ima say a 3900 v6 like wvumtnbkr put in the rx8. Cheap, light, powerful, efficient and compact. 

DocRob said:

I'm not really an advocate for EV swapping a classic car. But in the case of a DMC-12, a car that was futuristic and still is futuristic 40 years later...this is the way.

Target something 100-150kw range and you'll have more than enough power to really enjoy the car. Plus the INSTANT torque.

If I go EV, I might just be aiming for 121kw... 

Looks like there are a several DeLorean electric conversions to benchmark: reusing the transaxle; using bolt, leaf, or tesla drive units; one using Elaphe in-wheel motors (??!!!!).  EV conversion is still something like 10x a simple engine swap (10x cost, 10x time, 10x effort)?

This guy has an extensively documented conversion using a 2019 Bolt as a single donor, 3200# expected final weight.  It is not Binky, but 26 YT episodes starting in 2021, or a thread on diyelectriccar.  I think he has not explained how he did the halfshafts.  IMO, that is the lone (and very minor, and definitely not EV-specific) reason to keep the original transaxle.

I would put a LS with a DCT from a 135/335. Would be hilarious and the dct is becoming a common enough on swaps to make it seamless I would think.

In reply to Oapfu :

I'll have to check that out. The site looks to be offline right now, but I at one point read through all of Teslorean.com and what they'd done, which was in part why I'd decided that I didn't want to mess with the Tesla transaxle and would just keep the original 5-speed if I went the EV route. 

If you want it done within a reasonable time frame, go gasoline. Even as a fan of EVs, I'd only do an electric conversion if some criteria could be reached; off the back of my hand:

1. Forget about the OG transmission in the car with an EV swap. For the thousands you'll spend on a good motor to bolt to it, you could instead get a modern motor from a wrecked EV with it's inverter and make halfshafts- an electric motor bolted to a transmission cannot do regen, and the stock DeLorean transmissions are pretty weak and might not be able to take the sudden torque of an electric motor.
2. To add onto that, inverters are expensive and aftermarket stuff needs programming- while a Leaf motor and inverter combo (they're all one "unit") can be controlled via what's called "The Lebowski Brain" which is effectively hacks the motor and allows you to control it via several means.
3. Battery; liquid cooled and controlled batteries are just better, but old leaf cells bought secondhand are cheaper. What fits? What system can you charge it with? Can you use CCS? I know there's some projects through the SAE and such for a general charging system, but I'm not sure where they're at.
4. Range obviously. The DeLorean is heavy and not very aerodynamic, so you might need a bigger battery than you'd think.

Still tho, I am MORE than willing to spitball ideas! I know there's been a few DeLorean EV projects before, so measurements for things like battery packs and what to expect should be easily researched...

GIRTHQUAKE said:

 

1. Forget about the OG transmission in the car with an EV swap. For the thousands you'll spend on a good motor to bolt to it, you could instead get a modern motor from a wrecked EV with it's inverter and make halfshafts- an electric motor bolted to a transmission cannot do regen, and the stock DeLorean transmissions are pretty weak and might not be able to take the sudden torque of an electric motor.

Regen should be possible with a manual gearbox, although I would second that it really doesn't make sense to have multiple speeds on a street-only EV. It might be justifiable on an EV that sees track time.

GameboyRMH said:

GIRTHQUAKE said:

 

1. Forget about the OG transmission in the car with an EV swap. For the thousands you'll spend on a good motor to bolt to it, you could instead get a modern motor from a wrecked EV with it's inverter and make halfshafts- an electric motor bolted to a transmission cannot do regen, and the stock DeLorean transmissions are pretty weak and might not be able to take the sudden torque of an electric motor.

Regen should be possible with a manual gearbox, although I would second that it really doesn't make sense to have multiple speeds on a street-only EV. It might be justifiable on an EV that sees track time.

Can the forward gears in a trans take that?

Either way, if he went for something like a Leaf Motor unit it would give him a diff, motor, and inverter all within one package instead of multiple parts. It would also give him an integrated oil pump and coolant pump as well.